Elon Musk has said critics of his social media site X are looking for "any excuse for censorship", after its artificial intelligence (AI) chatbot Grok drew criticism over its use to create sexualised images of people without their knowledge or consent.

Ofcom says it is conducting an urgent assessment of X in response, with the backing of Technology Secretary Liz Kendall.

But the chairwomen of Parliament's technology and media committees have both said they are concerned that "gaps" in the Online Safety Act might hinder the media regulator's ability to deal with the matter.

X has now limited the use of AI image function to those who pay a monthly fee, a change dubbed by Downing Street as "insulting" to victims of sexual violence.

The BBC has seen several examples of the free AI tool undressing women and putting them in sexual situations without their consent.

Kendall said on Friday that she expects an update from Ofcom within days, and that it would have the government's full support should it decide to block X in the UK.

Musk reposted a number of messages on the site overnight criticising the government's reproval of Grok - including one which showed AI-generated images of Prime Minister Sir Keir Starmer in a bikini.

"They just want to suppress free speech," Musk wrote.

Ashley St Clair, the mother of one of Elon Musk's children, told BBC Newshour on Friday that Grok had generated sexualised photos of her as a child.

The conservative influencer said her image had been "stripped" to appear "basically nude, bent over", despite her telling Grok that she did not consent to the sexualised images.

St Clair, who filed a lawsuit against Musk in 2025 seeking sole custody of their child, accused the social media site of "not taking enough action" to tackle illegal content, including child sexual abuse imagery.

"This could be stopped with a singular message to an engineer," she said.

As of Friday morning, Grok was telling users asking it to alter images uploaded to X that "image generation and editing are currently limited to paying subscribers", adding users "can subscribe to unlock these features".

An Ofcom spokesperson said on Friday: "We urgently made contact [with X] on Monday and set a firm deadline of today to explain themselves, to which we have received a response.

"We're now undertaking an expedited assessment as a matter of urgency and will provide further updates shortly."

Ofcom's powers under the Online Safety Act include being able to seek a court order to prevent third parties from helping X raise money or be accessed in the UK - should the firm refuse to comply.

But Dame Chi Onwurah, chairwoman of the innovation and technology committee, said she was "concerned and confused" about how the matter is "actually being addressed", and has written to Ofcom and Kendall for clarification.

Dame Chi said it was "unclear" under the Online Safety Act whether the creation of such images using AI was illegal, as was the responsibility of social media sites for what was shared on their platforms.

"The act should really make something so harmful to so many people clearly illegal, and X's responsibility should be clear," she told BBC Radio 4's Today programme.

Caroline Dinenage, chairwoman of the culture, media and sport committee, likewise said she had a "real fear that there is a gap in the regulation".

"There are doubts as to whether the Online Safety Act actually has the power to regulate functionality - that means generative AI's ability to nudify someone's image," she told BBC Breakfast.

The use of Grok to generate non-consensual sexualised images has been condemned by politicians on all sides:

• Prime Minister Sir Keir Starmer called it "disgraceful" and "disgusting"

• Reform UK leader Nigel Farage said it was "horrible in every way" and that X "needs to go further" than the changes it had made to Grok on Friday, but he added that banning the platform would be an attack on free speech

• The Liberal Democrats called for access to X to be temporarily restricted in the UK while the social media site was investigated.

Elsewhere, Australia's Prime Minister Anthony Albanese said he agreed with Starmer that the material was "completely abhorrent".

"It, once again, is an example of social media not showing social responsibility," Albanese said, adding that Australia's digital safety commissioner was looking at the situation.

"Australians and indeed, global citizens deserve better."

Meanwhile, Grok was temporarily suspended in Indonesia on Saturday. The country's digital minister said "non-consensual sexual deepfakes [were] a serious violation of human rights, dignity and the security of citizens in the digital space".